Environmentally-Friendly Acrylates-Based Polymer Latices - Advanced Materials for Agriculture, Food and Environmental Safety - page 168

polymer also fuli lled the requirement of good quality trai c paint. Water-
thinned coatings [172] from BuA-2-HEMA-2-isocynatoethyl methacry-
late synthesized in the presence of (NH 4 )S 2 O 8 were transparent with good
water resistance.
A patent [173] claimed dispersions for the weather-resistant coatings
by the monomer mixtures containing MMA-Bu acrylate-acrylic acid.
h e i lms were dried at 80 C to give a clear, transpar-

ent, peelable, water-thinned, and good solvent resistant coating. In another
patent [174], aqueous acrylic polymer emulsions for sprayable clear coat-
ings have been synthesized by polymerization of acrylic acid-BA-tert.
BA-hydroxypropyl acrylate-MMA-Styrene. Emulsion of this polymer was
sprayed on primed steel, dried at room temperature and baked for 30 min
at 130

° C and aged at 40 °

C to give a 42-μm-thick i lm with 82-84% gloss.
h e 2-EHA is also incorporated with other monomers in latex coat-
ings. A combination of 2-EHMA with St and MMA is benei cial in
multilayer coatings with good appearance. Polyisocynate was used as
crosslinking agent in this combination [175]. h e compounds useful
for building exteriors contain emulsions of polymers having Tg of −10
to +50

°

C [176]. A copolymer combination of 2-EHA-acrylonitrile-AA
(Tg = −53

°

C), useful in l ooring coating, was proposed by Schwerzel et
al. [177]. A copolymer from MMA, 2-EHA and methacrylic acid was
synthesized by Takeuchi et al. [178]. When this copolymer was neutral-
ized with ethanolamine, coated on metal and dried, it gave a glossy, and
water-resistant coating.
A water-thinned metallic coating for automobile bodies was developed
by Sugiura [179] containing a thermosetting acrylic resin, a metallic pig-
ment, nonmeltable crosslinked resin particles and a metal silicate. h e
metallic coating was applied on a substrate, and a clear coating was applied
on the resulting uncured metallic coating, and both of the coatings were
heated for cure at once to give a surface with high gloss.
h e latex paints were considered free from any pollutants as they were
waterborne and the derived paint i lms were waterproof. h e paint was
easily formulated from an aqueous latex and a dispersion of pigment in
water. h e i lm-forming latexes are also used in l oor coatings (polishes),
printing inks, adhesives, paper overprint varnishes, carpet backing and
paper making.
Although a vast amount of literature is available on various types of
acrylic coatings, a systematic data is lacking for understanding the polym-
erization kinetics of the ef ect of higher acrylates [180-181] on crosslink-
able coatings based on methyl methacrylate and their performance on
various substrates. Since these coatings are widely used in industries, there

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